This particular bird is in its non-breeding plumage. you can expect them to look about like this (or with a little more white on their heads) by the time September begins to wind down. I think I prefer them in this plumage… but I am not a Murre. I really enjoy seeing them when the chance arrives. They are a fun little bird to watch as they dive deeply for fish and the occasional crustacean.
This image was taken using a 300mm lens with a 1.4x attachment for a total of 420mm. Shutter speed was fairly fast at 1/500th to capture any movement without blurring and to allow me to hand hold (so very difficult to use a tripod on a kayak). Aperture was stopped only partway down, so that the bird and only a narrow strip of water would be in focus, but with a slightly blurry foreground and background (aperture was set to f/9). ISO was set to compensate at 400.